Nearly Zero Energy Building Modeling and Design, for New and Existing Buildings

Course Leader: Dr Moga Ligia Mihaela

Home Institution: Technical University of Cluj-Napoca, Romania

Course pre-requisites: Thermotechnics of Constructions, Basic Building Design.

Course Overview
It is well known that the building sector accounts for around 40% of the global energy consumption, thus being one of the biggest generators of CO2 emissions. At a European level, starting from 31 December 2020, all new buildings must be designed considering the nearly Zero Energy Buildings (nZEB) criteria. Based on the requirements of the last energy performance of buildings Directive (EU) 2018/844, the same nZEB levels defined for new buildings, must also be met by existing buildings. Thus, the course will teach and guide you in a step to step approach of designing nearly Zero Energy Buildings and in energy retrofit of existing building to nZEB levels. The energy retrofit will present the approach of energy grading of buildings based on the energy performance calculation methodology.
The course will give an overview of the existing legislation and approaches in the field of buildings energetics. Passive and active measures in the design of new buildings and energy retrofit of existing buildings will be addressed. The imposed measures will be assessed from the perspective of the boundary climatic conditions where the building is located. Key points of several nZEB case studies from European countries will be discussed. At the end of the course participants will be able to apply the presented approaches in design stage of new buildings and energy retrofit activities.
The course is useful for students and other specialists interested in changing the design approach to nZEB.

Learning Outcomes
By the end of the course, students should be able to:
• Identify legislation in the field of buildings energetics (i.e. energy efficiency, energy performance of buildings)
• Identify passive and active measures suitable for the climatic context of the building
• Do a hygrothermal modeling of the building envelope using available design software
• Analyze the energy performance in the case of new buildings
• Analyze the energy performance for existing buildings
• Rate the energy performance of the building based on several energy consumptions (heating, cooling, domestic hot water, ventilation, lighting) and for the entire building
• Develop a suitable approach for reaching nZEB levels

Course Content
1. Legislation and design norms regarding buildings energetics: energy design of new buildings and energy retrofit of existing buildings

2. Types of high performance energy efficient buildings (i.e. low energy buildings, nearly Zero Energy Buildings, passive house, active house, net Zero Buildings, plus Energy Buildings)

3. Introduction to passive and bioclimatic design. Description of measures available to reduce the energy demand of a building (i.e. orientation, form, building’s fabric, solar gains, building mass, thermal optimized building components, energy efficient glazing, shading devices, air tightness, natural ventilation, green roofs and others).

4. Introduction to active measures (i.e. energy efficient equipment, mechanical ventilation with heat recovery, hybrid ventilation, LED lighting, PV panels, solar collectors, heat pumps and others)

5. Design approaches in the case of new buildings and existing buildings for reaching nZEB levels.

6. Presentation of case studies of best practices around European countries for nZEB buildings, in the case of new and existing buildings.

7. Calculation methodologies used in the evaluation of the thermo-energy performance of buildings. International and national available methodologies. Energy rating of buildings.

8. Modeling and assessment of the hygrothermal performance of building components and assessment of buildings energy performance using available software.

Course Lectures 1-2: 4 hours
Course Lectures 3: 4 hours
Course Lectures 4: 2 hours
Course Lectures 5-6: 4 hours
Course Lectures 7: 4 hours
Course Lectures 8: 4 hours

Each course will also have allocated the application part (i.e. seminars) in a total sum of 20 h.
Assessment of the building’s life cycle will not be addressed in the applications part, due to time constraint.

Instructional Method
The course will be divided in 22 h of lectures and 20 h of seminars.
The lectures will include theoretical knowledge regarding points 1-8. The knowledge will include up to date information regarding the addressed topics.
Seminars (i.e. application part) will include the approach of the two case studies: new building and existing building. Time will be allocated for the presentation and utilization of available commercial software. Basic applications will be simulated in order to develop the skills needed for elaborating the project. Excel and mathcad calculations will also be addressed for parts of the project.
Group project: students will be divided in groups (2 to 3 students) for more sustainable use of time, in order to reach the aim of the course applications. The group will address one of the two case studies (i.e. new or existing building) for the project elaboration.
The final class will include the submission and presentation of the developed projects.

Required Course Materials
Read the reference text:
OVERVIEW | Zero-Energy Buildings: does the definition influence their design and implementation?

Directive (EU) 2018/844 of the European Parliament and of the Council of 30 May 2018 amending Directive 2010/31/EU on the energy performance of buildings and Directive 2012/27/EU on energy efficiency

New buildings & NZEBs

NZEB, cost- and comfort-optimal retrofit solutions for an Italian Reference Hotel, Tiziana Buso, Cristina Becchio, Stefano P.Corgnati, Energy Procedia, Volume 140, December 2017, Pages 217-230

You are required to bring a laptop, so that you will be able to familiarize yourself with the software used in this course applications.

THERM software

WUFI® Plus

Quizzes: 2 quizzes used for assessing the gained knowledge during the course. Each quiz will represent 15% from the final grade.
Assignment: each group of students (i.e. 2-3 students/group) will choose for the final project, one of the two case studies: new building or existing building.
Presentation: final presentation and submission of the projects (65% of the final grade)
Feedback: providing feedback at other students presentation (5% of the final grade)